BleepingComputer.com: CPU fan semi-works and Power Off

My friend clean in computer case with a blow dryer. I think it's ESD but I'm not entirely sure. AFter blow drying, the first day, it power on and then shuts off if i don't select "return to last working windows (or something)" during the windows select screen. The next day, it starts to malfunctioning some more. TO turn it on, i would need to press the power button several time like an old vehicle needing to turn the key in the ignition a few times before engine starts. Now, the fan just turns on and that's it.

edit: the machine worked properly before. he used blow dryer set on cool. it turns on but get to that windows screen where it asks to repair, select OS, etc. i then need to select the previous working session (then dialogue box pops up to repair something). And then it turns on and works. But my car analogy still remains true. I need to press several time on the power button to have it turn completely on.

This post has been edited by tom rosali: 02 November 2009 - 09:05 PM

Did the machine work ok before he cleaned it? Was the cleaner a proper Air Duster used properly so it didn't discharge any liquid?

You also havent said if it does eventually work, just you need to keep stopping and starting it to get it going.

There's a few things that could cause erratic starting, assuming the air cleaning was done because of this?

It's like my computer is an old beat-up car that needs a few turn of the keys to start the engine. For example, those horror movies where the victim runs inside a car but it doesn't start, so the victim tries over and over. When the monster appears, the victim finally gets the car starting. My computer is kind of like that. I need to push the power button a few times before the computer gets enough juice to power all the hardware. Maybe "blow drying" all the dust out resulted in some fried chip/components?

This post has been edited by tom rosali: 02 November 2009 - 08:23 PM

Why did you blow the machine out anyway? Was it behaving oddly or was it just for something to do?

There is always a chance of a faulty component, maybe a power supply going off what you have said about its erratic starting. Do you have access to another one maybe off your friends machine?

My friend tried to get rid of the dust with a blow dryer. It was fine and behaving like normal before until he had to blow it with a damn blow dryer. Maybe using the blow dryer fried a chip or something on the motherboard? Can ESD take out a Power Supply?

cotesy, on Nov 3 2009, 06:12 PM, said:

This post has been edited by tom rosali: 03 November 2009 - 08:10 PM

Electrostatic Discharge can take out any circuit, but I find it unlikely to be the cause if all you've done is blow out the dust! It sounds like he tried to use a hair dryer?

There is always the chance that its coincidence that the PC is playing up now after cleaning it, just one of those things.

Sometimes, and it is an infrequent "sometimes", when blowing out a case you spin the internal fans fast enough to generate voltage and fry something on the motherboard. I toasted a fan header speed controller cleaning a fan with with a vac many years ago. Some have lost the motherboard entirely. Every once in awhile you hear about someone doing this, it's about as rare an event as can occur, but it does.

Yes. My mistake. It was a "HAIR DRYER".

The computer power on with the monitor not displaying anything. The monitor's power button is orange, meaning it is getting no signal from computer. The cpu fan is ON. The case fan is ON.

My only guess is that he might have "...generate voltage and fry something on the motherboard" or hair dryer might discharge static and got to the motherboard and now only some service can reach some of the components but not send signal to monitor. Also the power button led remain unlit even though the case fan/cpu fan is ON.

I test each component by removing it individually. I tested the RAM (2 pair - 4sticks. test a pair at a time), Graphic Card, disconnected optical drives, disk drives, BUT the same problem still lingers on. The first couple of days the computer would work like normal except having to power it on took a few press of the "power button" but it worked. Now, I can't even get the monitor to display anything, let alone I can't hold the power button for 10 second and power down the computer. Any ideas? Thanks.

cotesy, on Nov 3 2009, 08:28 PM, said:

Sounds like the PC is going down fast!

You need to check the Capicators on the motherboard, its one of the first things I look for when the machine is behaving irratically as yours is.

Do you know what a Capacitor is? The Capacitors on the motherboard look like small Barrels standing on the board where the top of them looks to have a line or a 'K' on the top. These eventually fail, especially on overheated motherboards. The way to tell is any discoulouration or if they start to become domed on the top (they should be flat). Newer motherboards use Solid Caps as they call them rated at 50k hours so they know they are a problem.

I've attached a photo of a typical set of caps, the arrowed ones are bad!

If yours are showing signs of the doming effect, the power regulation on the motherboard is all over the place and unless you obtain new ones at the right values and are handy with a soldering iron, the board is ready for the bin.

@cotesy, thanks. i just checked the capacitor and found that none was discolored or domed. so would it be wise to think that somehow the motherboard is failing me and replace it if there's no other solution?